Prior to applying a new tread to a tire carcass, it is necessary to prepare the surface of the carcass so that it is substantially uniform and has the proper shape and condition for receiving the tire retread material. It has been customary for a number of years to use a rotating hub with a large number of rasp blades mounted on the hub for cutting and buffing the surface of the tire carcass to prepare such surface for receiving the retread material. Such rasp blades have been used in numerous configurations and shapes in the prior art, examples of which are found in U.S. Pat. Nos. 3,680,185; 3,082,506; 2,896,309; 4,021,899; 3,879,825; 4,091,516; and Australian patent No. 442,257. So far as is known, the earliest rasp blade having rasp teeth made in sets of four with two pairs of teeth facing at opposite angles of inclination to each other with recesses between the teeth is in U.S. Pat. No. 3,680,185. The present invention is an improvement on the tire rasp blade of U.S. Pat. No. 3,680,185 in that it has more sets of teeth, and more metal left in each tooth, adding strength to minimize breakage of the teeth.